I'm not sure of the technical reasons, many of the files in the new format do not play on my machines. Would someone list the players needed to view the 'improved' movie files. Preferably free or open source. Thanks.
The GOM player works and it's free. Personally I love GOM for its wide variety of useful features and ease of use. It plays every video format I've encountered except DRM protected WMV. For these reasons it's my default multimedia player.